I have been having pretty bad wastegate rattle at idle/acceleration lately, so i decided to mess around with the WGPositions. What i noticed when i datalogged my car was that i was getting a constant 1.8PSI of boost, even off-throttle/idle. When i played with the throttle a little, the boost built to 1.9 PSI and then fell back to 1.8PSI. When heavily on throttle, the car built boost normally and stopped building boost at 17PSI (the dead-line i set it at).

I recently installed AA DPs. Is it possible that one of the turbos is building boost constantly due to the v-band clamp stopping the actuator? Could this also be the cause of my rough acceleration/idle/wastegate rattle?

Try setting the wastegate position to 30 in the global user adjustable parameters and see if that helps. If so, adjust it back 5% at a time until you have issues again so you know where to set it. Good luck.

N54's are designed from factory to have slight pressure at idle IF the wastegates are closed. The software keeps the wastegates open during idling. Change that and you have boost. Small turbos bro.

Actually depends on the software level. The later cars have the wastegates closed at idle for less turbo lag. My early N54 (1/07) has the wastegates open at idle, as I have the lovely 6mm-pin early turbo design that likes to rattle.

Regardless of wastegate position, the bypass valves should be pulled open by the vacuum in the intake manifold at idle. BMW definitely didn't engineer the car to have positive pressure in the manifold at idle and cruise.